Roller blind



FIG. 1 is a front elevational view of a roller blind showing our new design;

FIG. 2 is a left side view elevational view thereof;

FIG. 3 is a right side view elevational view thereof;

FIG. 4 is a rear elevational view of part of the roller blind in a closed position;

FIG. 5 is a top plan view of part of the roller blind as shown in FIG. 4; and,

FIG. 6 is a bottom plan view of part of the roller blind as shown in FIG. 4. 

The ornamental design for a roller blind, as shown and described. 